TW593493B - Cellulose ester film - Google Patents

Abstract

A cellulose ester film is disclosed which comprises a polyhydric alcohol ester, which is an ester of one or more kinds of monocarboxylic acids with an aliphatic polyhydric alcohol, wherein the cellulose ester film has a water vapor transmission rate of from 20 to 260 g/m<2>.24 hours measured under conditions of 25 DEG C and 90% RH.

Description

593493 A7 __B7 V. Description of the Invention (1) Field of the Invention The present invention relates to a cellulose ester film, and particularly to a cellulose ester film used in a polarizing plate and a protective film for a polarizing plate. BACKGROUND OF THE INVENTION Recently, reductions in thickness and weight of information processing devices such as notebook personal computers have been developed. In parallel with this development, polarizing plate protective films used in liquid crystal displays have eagerly sought to make them thinner. Cellulose ester films are commonly used in polarizing plate protective films. However, simple reductions in the thickness of cellulose ester films have proven to cause different problems. Cellulose triacetate films used in polarizing plate protective films contain plasticizers to improve film flexibility or water vapor permeability. However, a simple reduction in the thickness of the cellulose triacetate film increases water vapor permeability, reduces water resistance, and sometimes destroys polarizing films or adhesives for making polarizing plates. In order to compensate for the reduction in thickness, it is thought that the amount of plasticizer added to the film should be increased in proportion to the reduction in thickness. However, it has been found that a simple increase in the amount of plasticizer added does not sufficiently improve the water vapor permeability, causing and causing new problems such as damage to retention. The weight of the film is reduced under high humidity and temperature, because additives such as plasticizers can volatilize or precipitate. The property of additives such as plasticizers in the film is called retention. The retention property of a general cellulose ester film is low, which reduces the performance of a liquid crystal display using the cellulose ester film. There is a technique in Japanese Patent OPI Publication 1 1 0 9 2 5 74, in which citrate is used, and there is a technique in Japanese Patent 0.1, Publication 1 1-1 1 4 4 4 5 in which pentaerythritol ester is used National Standard (CNS) A4 (210X297 mm) of this paper (Please read the precautions on the back before filling out this page) Binding. Order printed by the Intellectual Property Bureau Staff Consumer Cooperatives of the Ministry of Economy 593493 Α7 Β7 V. Invention Description (2 ) (Please read the notes on the back before filling out this page) or dipentaerythritol ester, there is a technology in Japanese Patent OPI Announcement 1 1-2467 04, which uses glyceride, or in Japanese Patent ◦ P. I. Announcement There is a technique in which diglycerides are used. However, these techniques are not sufficient to improve water vapor permeability and disrupt retention. Summary of the Invention An object of the present invention is to provide a cellulose ester film having an excellent water vapor transmission rate and excellent retention properties. DETAILED DESCRIPTION OF THE INVENTION The above object of the present invention has been achieved by the following components: 1. A cellulose ester film comprising a polyol ester, the polyol ester is an ester of one or more monocarboxylic acids and an aliphatic polyol, wherein the fiber The plain film has a water vapor transmission rate of 20 to 260 g / rri · 24 hours, which is measured at 25 ° C and 90% R%. 2. The cellulose ester film of item 1, wherein the cellulose ester film has a retention of 0.0 to 2.0%. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 3. The cellulose ester film of item 1, in which the monocarboxylic acid has an aromatic ring or a cycloalkyl ring in its molecular structure. 4. The cellulose ester film of item 1, wherein the aliphatic polyol has a hydroxyl number of 2 to 20. 5. The cellulose ester film of item 1, wherein the cellulose ester film has a thickness of 10 to 6 5 // m. 6. The cellulose ester film of item 1, in which the aliphatic polyhydric alcohol is applied in accordance with the Chinese National Standard (CNS) A4 specification (21 ° '297 mm) -07875 -5 593493 A7 B7 from the following standard of this paper: V. Description of the invention ( 3) Formula (1): Formula (1) (R 1; (〇Η) The Ri * η-valent aliphatic group is printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs, and η represents an integer of not less than 2. 7. The cellulose ester film of item 6, wherein the η-valent aliphatic group is selected from the group consisting of alkylene, alkenyl, alkynyl, cycloalkyl, and alkyltriyl groups. 8. The cellulose ester film of item 1, The polyol ester has a molecular weight of 300 to 150,000. 9. The cellulose ester film of item 1, wherein the total number of aromatic rings or cycloalkyl rings in the molecular structure of the polyol ester is not less than 3. The present invention It will be described in detail as follows. The present inventors have extensively studied to achieve the foregoing object, and as a result, they have succeeded in obtaining a cellulose ester film that provides a satisfactory water vapor transmission rate and superior retention properties even when using this cellulose The optical film of the ester film has a reduced thickness. That is, the above of the present invention This has been achieved with cellulose ester films which include aliphatic polyols and esters of one or more monocarboxylic acids and have a water vapor transmission rate within the range defined in the present invention. In the present invention, the polyol ester The functions are not fully classified, but it is believed that the amount of plasticizer added can be reduced by the addition of polyol esters. The retention property referred to in the present invention means that additives such as plasticizers in the film are at high temperature and high humidity The property of being retained in the film under conditions without precipitation or volatilization. In the present invention, the retention of the film is obtained by the following procedure: The film sample is left to stand at 23 ° C and 55% RH for one day and weighed. Sample After heat treatment, the samples are stored at 80 ° C and 90% R Η (Please read the precautions on the back before filling out this page) Installation, 1T This guide is applicable to China National Standard (CNS) Α4 specification (2ΐ) 〇χ 297mm) Si 8 7 7 -6- 593493 A7 B7 V. Description of the invention (4) The next two weeks. The obtained sample is left to stand at 2 3 ° c and 5 5% RH for one day, and then weighed. Stay The property is calculated by the following formula: (Please read the precautions on the back before (Write this page) Retention (%) = (film weight before heat treatment and film weight after heat treatment) X 1 0 0 / film retentivity before heat treatment is advantageously not more than 2.0%, and more advantageously not more than 1 _ 0%, even more advantageously not greater than 0.5%, and most advantageously not greater than 0.1%. The water vapor transmission rate referred to in the present invention is at 25 ° according to the method described in j I s Z 0208. Measured at 90% and 90%. Secondly, the polyol ester used in the present invention will be described in detail. The polyol ester referred to herein contains an ester of an aliphatic polyol and one or more monocarboxylic acids. Alcohol) The aliphatic polyol used in the present invention contains an alcohol having two or more hydroxyl groups, which is represented by the following formula (1): (1) R1- (〇H) n wherein Rig η valence organic group, and η represents an integer of not less than 2. Examples of the η-valent organic group include an alkylene group (such as methylene, ethylidene, trimethylene, tetramethylidene, etc.), an alkenyl group (eg, vinylidene, etc.), and an alkylene group (eg, vinylene) Radicals, etc.), cycloalkylenes (eg, 1, 4 ring cyclohexyl radicals, etc.), and tertiary radicals (eg, 1,2,3-tributene III radicals, etc.). The above η-valent organic groups include those having substituents (for example, hydroxyl paper # Chinese National Standard (CNS) A4 specification (210X297 mm) 593493 A7 B7 5. Description of the invention (5) ®, alkyl, halogen atom, etc.). ",, η" is advantageously 2 to 20, more advantageously 2 to 15, and most (please read the notes on the back before filling out this page). The integer is 3 to 10. Advantageous examples of polyols Including aldonitol, arabitol, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2-propylene glycol, 1, 3 ~ propylene glycol, dipropylene glycol, tripropylene glycol, 1, 2- Butanediol, 1,3-butanediol, 1,4-butanediol, dibutanediol, 1,3,4 ~ butanetriol, 1,5-pentanediol, 1,6-hexanediol , Hexanetriol, galactitol, mannitol, 3-methylpentane-1, 3, 5-triol, pinacol, sorbitol, trimethyl alcohol propane, trimethyl alcohol Ethane and xylitol. Triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, sorbitol, trimethylol propane, and xylitol are particularly advantageous. (Monocarboxylic acid) Ministry of Economy Wisdom The monocoic acid used for preparing the polyhydric alcohol in the present invention printed by the Consumer Cooperative of the Property Bureau is not particularly limited. Monocarboxylic acids include aliphatic monocarboxylic acids, alicyclic monocarboxylic acids, and aromatic monocarboxylic acids, and Cyclic monocarboxylic acids and aromatic monocarboxylic acids are advantageous in terms of improving water vapor transmission rate and retention. Examples of advantageous monocarboxylic acids include the following compounds, but the present invention is not limited thereto. Aliphatic monocarboxylic acids are Having, linearly or branched fatty acids, advantageously 1 to 32, more advantageously 1 to 20, and most advantageously 1 to 10 carbon atoms. In providing increased compatibility with cellulose esters, Acetic acid is advantageous-8- This document describes the National Standard (CNS) A4 specification (210X297 mm) 593493 A7 __B7_ 5. In the description of the invention (6), the combined use of acetic acid and other monocarboxylic acids is more advantageous. (Please read the notes on the back before filling this page.) Favorable examples of aliphatic monocarboxylic acids include saturated fatty acids such as acetic acid, propionic acid, butyric acid, valeric acid, hexanoic acid, heptanoic acid, nonanoic acid, capric acid, 2-ethyl Base-hexadecanoic acid, acetic acid, lauric acid, tridecyl acid, myristic acid, pentadecanoic acid, palmitic acid, heptadecanoic acid, stearic acid, nonadecanic acid, arachidic acid, mountain Osmic acid, ossetanoic acid, ossanoic acid, ossanoic acid, ossanoic acid, triosanoic acid or shellac Acids; and unsaturated fatty acids such as undecylenic acid, oleic acid, sorbic acid, linoleic acid or arachidic acid. These include those with substituents. Favorable examples of alicyclic monocarboxylic acids include cyclopropanecarboxylic acid, cyclohexane Carboxylic acids, cyclooctane carboxylic acids, and derivatives thereof. Favorable examples of aromatic monocarboxylic acids include benzoic acid, alkyl-substituted benzoic acids such as toluic acid, and aromatic monocarboxylic acids having two or more benzene rings such as Biphenylcarboxylic acid, naphthoic acid, or tetrarin carboxylic acid and its derivatives. Benzoic acid is particularly advantageous. (Polyol ester) The molecular weight of the polyol ester used in the present invention is not particularly limited, but is advantageously 300 To 1500, and more advantageously 350 to 750, printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. Polyol esters having higher molecular weights are advantageous in terms of retention, and polyol esters having lower molecular weights are advantageous in terms of water vapor transmission rate and its compatibility with cellulose esters. The monocarboxylic acid used for preparing the polyol ester in the present invention may be used alone or as a mixture of two or more kinds thereof. All the hydroxyl groups of the polyol can be esterified or a part of the hydroxyl groups of the polyol can be esterified to retain the free hydroxyl groups 05893493 A7 B7 V. Description of the invention (7) (Please read the precautions on the back before filling this page) In the present invention, the polyol ester advantageously has an aromatic ring and / or a cycloalkyl ring in the molecule. More advantageously, the polyol ester in the present invention has a total of not less than 3 aromatic rings and / or cycloalkyl rings, that is, the polyol ester in the present invention has three or more aromatic rings Rings, those with three or more cycloalkyl rings, or those with three or more aromatic rings and ring base rings. In this paper, regarding aromatic rings, a fused aromatic ring (such as a naphthalene ring or anthracene ring) is an aromatic ring. Examples of the polyol in the present invention are explained below. Printed by the Employees' Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 007882_ This paper size applies to the Chinese National Standard (CNS) A4 specification (210X297 mm) -10- 593493 A7 B7 V. Description of the invention (8) 2 3 4 C4H9—gO— (CH2 ) 2—〇— (CH2) 2—0— (ch2) 2—0-brother c4h9 0 &quot;

0 5 〇4 9-5-〇 十 CH2-CH2-g-c4h9 〇4 0 6 C8H17 ~ C-〇 ^ CH2-CH2-〇jy-C ~ C8H17—ο 4 ο 7 CHrCHro) ^-^) ο 8 0 ~ π- ° · -ch2ch2ch2 ~ o (Please read the precautions on the back before filling in this page) One pack · Order 9 C4H9 ~ C-0 ^ CH2CH2CH2 ~ 0 ^-* C ~ C4Hg 〇3 〇 10 11 〇 〇8 ^ 17 ~~ 〇 ~ 〇-ο -〇 + 丨 • CH2CH2CH2—ο) τ? Ι CH2CH2CH2—ο- C-C8H17 12 〇-S- ° -f CH2? H- ° hi o ch3 ο χ = == / Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 13 C4H9 一 C—〇-ο -c-c4h9ο CH2CH—ο- ch3 C8H17 ~ C-〇 ^ CH2CH—O ^ jC-CsHn o ch3 丨 丨 15 (VC ~ 〇4-CH2CH—o- ch3 o 14 o W Γ '

Paper House Standard (CNS) A4 specification (210X 297 mm 11-593493 Five printed by the Intellectual Property Bureau of the Ministry of Economic Affairs, Consumer Cooperatives printed invention description (9) 16 18 〇π CH2 * -〇 ~ C ~ CgH ^ ch3ch2-ch2-〇 1-c8H17I ο CH2-0—C—CgHiTII 〇 20 〇 y, ch2-och ^ ~ \ CH3CH2—C—CH2—〇—C—CHq II ^ ο CH2-〇—C—CH3 II ο

CH3CH2-- CH2-0-C— ^ ^ 〇 \ = / CH2 &quot; · 0 ~ C y II \ = J 0

ch2-oh (Please read the precautions on the back before filling this page) One pack · 1T -P. Home Standard (CNS) A4 Specification (210X297 mm) 12-593493 A7 B7 V. Description of Invention (10) Ministry of Economy Printed by the Intellectual Property Bureau Staff Consumer Cooperative

(Please read the precautions on the back before filling this page) This paper stomach, Zeng Yu case_National Standard (€ milk) 8 4 specifications (210 father 297 mm) 13- 593493 A7 \ χ Β7 V. Description of the invention (11)

CH3—CH2—C—CH2—〇-C— (\ CH3—CH2—C-CH2—0—C— () a Fei 7 CH: ch2 --------- install-(please first (Please read the notes on the back and fill in this page) 33 、 Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs

^ Ning National Standard (CNS) A4 specification (210X297 mm) -14- 593493 A7 _____B7__ V. Description of the invention (12) (Please read the notes on the back before filling this page) Polyols in cellulose esters The added amount of the ester is advantageously 3 to 30 wt%, more favorably 5 to 25 wt%, and most favorably 5 to 20 wt%, based on the weight of the cellulose ester. (Cellulose ester) The cellulose ester used in the present invention is advantageously a low-carbon fatty acid ester of cellulose. The low-carbon fatty acid used in the preparation of the low-carbon fatty acid ester of cellulose contains a fatty acid having a carbon number of not more than six. Examples of low-carbon fatty acid esters of cellulose include cellulose acetate, cellulose propionate, cellulose butyrate, and mixed fatty acid esters of cellulose, such as cellulose acetate propionate, or fiber Acetoacetate butyrate is as disclosed in Japanese Patent O.P.I. Publications 10-45804 and 8-231761 and U.S. Patent No. 2,31,905. Among the low-carbon fatty acid esters of these celluloses, cellulose triacetate or cellulose acetate propionate is particularly advantageous. The cellulose triacetate printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs has a degree of polymerization of favorably 2 500 to 4 0 and advantageously 54.0 to 62.5%, and more favorably 58.0 to 6 2 · 5% The average gadolinium acetate (acetic acid content) is based on the strength of the film. The most favorable low-carbon fatty acid ester of cellulose is a fluorenyl group having 2 to 4 carbon atoms as a substituent, and simultaneously satisfy the following formulae (I) and (Π): Formula (I) 2.6SX + YS3. 0 Formula (π) 0 ^ X ^ 2. 5 where X is the degree of substitution of ethynyl, and Y is the substitution of propionyl or butylsulfonyl ^^ Fill in 3 Rongheng National Standard (Milk) 8 Specification (210/297 (Mm) 593493 A7 B7 5. Description of the invention (13) degrees. Among cellulose esters, cellulose acetate propionate is more advantageous, and cellulose acetate propionate that satisfies 1.9 &apos; XS2.5 and 0.isys 0.9 is most advantageous. The free hydroxyl group is present where it is not substituted by a fluorenyl group. These cellulose esters can be synthesized by a general synthetic method. In the present invention, cellulose esters synthesized from raw materials such as cotton linter, tree pulp and kenaf can be used alone or in combination. Particularly advantageously, cellulose esters synthesized from raw materials such as cotton linters (hereinafter also referred to as cotton linters) are used alone or in combination. (Manufacturing method of cellulose ester film) The manufacturing method of the cellulose ester film of this invention is demonstrated below. The cellulose ester film of the present invention is produced by casting a dopant in which the cellulose ester is dissolved in a solvent on a support and drying. The dopant may optionally contain different kinds of additives. Advantageously, the cellulose ester concentration of the dopant is higher because the load of the dopant cast dried on the carrier is reduced. Too high concentration of cellulose esters of dopants will increase the filtration load during filtration, leading to a reduction in filtration accuracy. In view of the above, the cellulose ester concentration of the dopant is advantageously 10 to 30 wt%, and more advantageously 15 to 25 wt%. The solvent used in the dopant of the present invention may be used alone, but in view of production efficiency, it is advantageously used in the form of a mixed solvent of a good solvent of cellulose ester and a poor solvent of cellulose ester. Advantageously, the good solvent content of the mixed solvent is advantageously 70 to 90 wt%, and the poor solvent content of the mixed solvent is

National Standard (CNS) of this paper A4 specification (210X297mm T (please read the precautions on the back before filling out this page) Binding and printing Printed by the Intellectual Property Bureau Staff Consumer Cooperatives -16- 593493 Α7 Β7 V. Description of the invention ( 14) The amount is advantageously 2 to 30 wt%. In the present invention, a good solvent is defined as a solvent alone capable of dissolving cellulose ester, and a poor solvent is defined as a solvent alone which cannot swell the cellulose ester alone or cannot dissolve the cellulose ester. Therefore, the solvent is a good or poor solvent for cellulose esters depending on the average hydrazone acetate of the cellulose ester used. For example, acetone is a good solvent for cellulose esters with an average hydrazone acetate content of 50%, but it has 6 ◦ Poor solvent for cellulose esters of average rhenium acetate. Examples of good solvents used in the present invention include organic halogen-containing compounds such as dichloromethane and dioxane. Cellulose acetate propionate is preferred Solvents include dichloromethane, acetone, and methyl acetate. Examples of poor solvents used in the present invention include methanol, ethanol, n-butanol and cyclohexane, propane, and cyclohexanone. When preparing the above-mentioned dopants The cellulose ester is dissolved in a solvent according to a common method, and the cellulose ester is favorably dissolved in the solvent under an increased pressure from the atmospheric pressure boiling point of the solvent to a temperature at which the solvent does not boil, with stirring, because the undissolved Substances such as gel lumps are not produced. It is also a method in which the cellulose ester is mixed with a poor solvent to swell the cellulose ester, and then a good solvent is added to dissolve the cellulose ester. The pressure application is carried out by: using pressure Combining an inert gas such as nitrogen into the tank or increasing the solvent vapor pressure in the tank by heating. Heating is advantageously performed outside the tank, and a sleeve-type tank is advantageous because the heating temperature is easy to control. The solubility and heating temperature are advantageously in the range of the boiling point of the solvent used at normal pressure to the temperature at which the solvent does not boil. Too high is the paper standard (CNS) A4 (210X297 mm) (please read the note on the back first) Please fill in this page again)-Packing. Order printed by the Intellectual Property Bureau of the Ministry of Economic Affairs's consumer cooperatives 534993 A7 _ B7 V. Description of the invention (15) The heat temperature needs to be higher Pressure results in poor production efficiency. The heating temperature is advantageously between 45 and 120 ° C, more advantageously between 60 and 110 ° C, and still more advantageously between 70 and 105 ° C. The applied pressure is adjusted so as not to boil the solvent at the set temperature. Second, the cellulose ester solution is filtered through a suitable filter such as filter paper. The filter medium used is advantageously smaller in absolute filtration accuracy to remove Insoluble matter. The absolute filtration accuracy of the size may clog the filter media, and therefore, the filter media for cellulose ester solutions or dopants is advantageously to have no more than 0.008 mm, and more advantageously, 0.001 to 0. 008mm, and more favorable absolute filtering accuracy of 0.003 to 0.006 mm. The material of the filter medium is not particularly limited, but is favorably such as polypropylene or Teflon (R) or metal such as stainless steel having a non-woven fabric. Filtration of the dopant is performed using a general method. Filtration of the dopant is advantageously carried out at an increased pressure from the atmospheric boiling point of the solvent to a temperature at which the solvent does not boil, because the increase in filtration pressure is small. The temperature during filtration is advantageously 45 to 120 ° C, more advantageously 45 to 70 ° C, and still more advantageously 45 to 55 ° C. The filtration pressure is advantageously lower. The filtration pressure is advantageously not greater than 1.6 X 1 0 6 P a, more advantageously 1.2 x 10 6 P a, and most advantageously not more than 1. α X 1 0 6 P a. (find the search method) The carrier used in the dopant casting method is a circular tape or drum-shaped paper; CNS Α4 size (210X297 mm) (Please read the precautions on the back before filling (This page) One piece · Order printed by the Employees 'Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs-18- Printed by the Employees' Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 534993 A7 B7 ___ 5. Description of the invention (16) The surface of the carrier is reflective. Advantageously, the surface temperature of the support during the casting method is in the range of 0 ° C to less than the boiling point of the solvent used. The higher the temperature, the more advantageous in terms of drying speed. However, its too high temperature can lead to foaming or flatness of the film. The surface temperature of the carrier is advantageously 0 to 50 ° C, and more advantageously 5 to 30 ° C. The method of controlling the temperature of the carrier is not particularly limited, but there is a method of blowing hot or cold air to the carrier or a method of bringing the carrier into contact with a tank containing hot water. The latter method is advantageous because the heat conduction is effectively performed and the time required to heat the carrier at a constant temperature is short. In the foregoing method, hot air having a temperature higher than a desired temperature may be used. In order to obtain good flatness of the carrier, when the film is peeled from the carrier, the residual solvent content of the film is advantageously 10 to 120%, more advantageously 20 to 40% or 60 to 120%, and most favorably 20 To 30% or 70 to 110%. In the present invention, the residual solvent content of the film is represented by the following formula: Residual solvent content = (film weight before heat treatment-weight after heat treatment) X 1 00 (%) / (film weight after heat treatment) where the heat treatment is at 1 1 Heat the film at 5 ° C for 1 hour. In the cellulose ester film drying method, the cellulose ester film peeled from the carrier is further dried to give a residual solvent content of not more than 3 wt%, and more preferably not more than 0.5 wt% in the film. In the film drying method, the film is usually conveyed on a drum or in a tenter while being dried. 007831 This paper size applies Chinese National Standard (CNS) A4 specification (210X297 mm) (Please read the precautions on the back before filling out this page)-Packing ·, 11 -19- 593493 A7 ___ _B7_ V. Description of the invention (17) The film is dried, and the film still has the same. Drying film gas, infrared light, convenience is good. The temperature is gradually raised in the range of 50. In order to make use of the extremely small, it will destroy water, which is more advantageous (please read the precautions on the back before filling this page). )-1. When improving the dimensional stability of the film, it is advantageous to maintain the film width or stretch the film when it is thin. The residual solvent content is quite high according to the tenter method. The method for peeling the film from the carrier is not particularly limited. , But often use heated air heated drum or microwave. Given the heated air. Advantageously, the drying temperature is in the range of 40 to 140 ° C. In view of the dimensional stability of the film, it is more advantageous to dry it gradually in the range of 140 ° C. The smaller thickness of the cellulose ester film is advantageous because the panel or liquid crystal display is thinner. However, the film thickness is the rate of vapor transmission or the tear strength of the film. In order to overcome the thickness of the vitamin ester film is advantageously 10 to 6 5 // m, 20 to 60 0 // m and even more advantageously 35 to 50 0 // m (use) employees of the Intellectual Property Bureau of the Ministry of Economic Affairs In view of the low water vapor transmission rate and superior dimensional stability, the consumer cooperative prints the cellulose ester film of the present invention to be advantageously applied to liquid crystal display materials. A liquid crystal display material is a material used in a liquid crystal display, for example, a polarizing plate, a protective film for a polarizing plate, a phase difference film, a reflective plate, an angle-of-view increasing film, an anti-flicker film, a non-reflective film, or an antistatic film. The cellulose ester film of the present invention is particularly advantageously applied to a polarizing plate or a protective film for a polarizing plate. The polarizing plate can be prepared by a general method. For example, there is a method in which the cellulose ester film of the present invention is subjected to alkali saponification, and the obtained film is adhered to both sides of the polarized film through a fully saponified aqueous solution of polyvinyl alcohol. The paper standard (CNS) A4 (210X297) -20-20593493 A7 B7 V. Description of the invention (18) The polarizing film has been prepared by impregnating a polyvinyl alcohol film in an iodine solution and stretching the film. Alkali saponification means the following treatment. Among them, cellulose ester The film is immersed in a strong alkaline solution at a high temperature to enhance the wettability of the film to an aqueous adhesive and provide good adhesion to the film. In the present invention, the retardation R in the plane of the cellulose ester film obtained above. (Nm) is as small as possible. The retardation R in the plane (nm) is advantageously not more than 100 nm, more advantageously not more than 10 nm and most advantageously not more than 5 nm. When cellulose ester is used When the film acts as a phase difference film, Ro (nm) is advantageously 30 to 100 nm. In the present invention, the three-dimensional refractive index of the cellulose ester film at a wavelength of 590 nm is measured by an automatic birefringence meter and a retardation phase angle of 0 is obtained.i and reflection index NX and N y, the retardation in the plane R 〇 of cellulose ester film can be calculated as follows: R 〇 二 (Nx-Ny) xd where Nx shows the mechanical direction parallel to the film (equivalent to the long axis direction) ) And N y indicate the refractive index in a direction perpendicular to the mechanical direction of the film, and d indicates the thickness (η m) of the film. Advantageously, in the present invention, the mechanical direction of the film and the retardation axis direction The included angle is closer to 0 °, + 90 ° and -90 °. In this example, when this cellulose ester film is used as a polarizing plate protective film, it helps the polarizing angle of the polarizing plate The retardation phase axis referred to in this article includes the direction that provides the maximum refractive index in the plane of the film. Furthermore, θι (radian) (derived from 6. °) and advantageously in the plane RQ The blockage satisfies the following formula: National Paper Standard (CNS) Α4 Specification (210X297 mm) ~ — -21-(Please read the precautions on the back before filling out this page) • Binding and Ordering Staff Consumer Cooperatives, Intellectual Property Bureau, Ministry of Economic Affairs Printing 593493 A7 ___B7 _ _ V. Description of the invention (19) P ^ l-sin2 (2 ^ i) -sin2 (^ R〇 / ^) (Please read the precautions on the back before filling this page) In the above formula, P is advantageously not less than 0 · 9 9 9 〇 〇, It is more advantageously not less than 0. 9 9 9 9 0, even more advantageously not less than 0.9 9 9 9 5 and most favorably not less than 0.9 9 9 9 9. λ indicates the measurement of the three-dimensional refractive index for obtaining The wavelengths of the light used by R 0 and 0 ^ are in the range of 380 to 650 nm. Advantageously, the above formula is satisfied when it is again 590 n m, and more advantageously, when λ is not less than 400 n m, the above formula is satisfied. The present invention will be explained in detail as follows. (Additive) The cellulose ester film of the present invention may optionally contain a plasticizer, an ultraviolet light absorber, a matting agent, and a dye. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs In the present invention, a polyol ester and a general plasticizer may be used in combination. Generally, the amount of plasticizer added is advantageously zero or less when the polyol ester is not used. The added amount of general plasticizers in cellulose ester films is advantageously from ◦ to 30% by weight, more favorably from 0 to 25% by weight, and even more favorably from 0 to 20% by weight. The plasticizer used in the present invention is not particularly limited, but is favorably a phosphate plasticizer, a phthalate plasticizer, or a glycol plasticizer. Examples of the phosphate plasticizer include triphenyl phosphate, tricresyl phosphate, toluene diphenyl phosphate, octyl diphenyl phosphate, diphenyl biphenyl phosphate, trioctyl phosphate, or tributyl phosphate. Examples of phthalate plasticizers include diethyl phthalate, dimethoxyethyl phthalate, dimethyl phthalate, dioctyl phthalate, dibutyl phthalate, or -22- paper, ^ Bao national standard (Yi Bi) VIII specifications (210 ~ 297 mm) 593493 A7 B7 5. Description of the invention (2) Di-2-ethylhexyl phthalate. Examples of the glycol ester plasticizer include butyl phthalofluorenyl butyl glycolate, ethyl phthalofluorenyl ethyl glycolate, or methyl phthalofluorenyl ethyl glycolate. These plasticizers can be used alone or in combination. The ultraviolet light absorber used in the present invention is advantageously an ultraviolet light absorbent which has superior absorption to ultraviolet light having a wavelength of less than 370 nm and has reduced absorption to visible light having a wavelength of more than 400 nm. Display the LCD image in a clear way. The ultraviolet light absorber advantageously has a transmittance of not more than 10%, more preferably not more than 5%, and most advantageously not more than 2% at 37 nm. The ultraviolet light absorber added to the cellulose ester film of the present invention is advantageously an ultraviolet light absorber having two or more aromatic rings in its molecular structure. The ultraviolet light absorber used in the present invention is not particularly limited, and examples of the ultraviolet light absorber include an oxybenzophenone compound, a benzotriazole compound, a salicylate compound, a benzophenone compound, and a cyano group. Acrylate compounds, nickel complex compounds, and inorganic powders. As the ultraviolet light absorber favorably used in the present invention, a benzotriazole or benzophenone compound-type ultraviolet light absorber is favorably used, which has high transparency and reduces the damage of a polarizing plate or a liquid crystal. A benzotriazole-type ultraviolet light absorber is particularly advantageously used, which reduces unwanted coloration. Typical examples of the ultraviolet light absorber used in the present invention advantageously include TINUBIN 109, 171, 326, 327, and 328 (each produced by Ciba Specialty Chemicals Co., Ltd.), and the present invention is not limited thereto. These UV absorbers can be used alone or as a mixture of two or more ------- (Please read the precautions on the back before filling out this page) Ordered by the Intellectual Property Bureau of the Ministry of Economy Staff Consumer Cooperatives-23- 593493 A7 _B7 ___ V. Description of the invention (21) (Please read the precautions on the back before filling this page) Type use. As for the ultraviolet light absorbent, a polymerized ultraviolet light absorbent is also advantageously used. The polymerized ultraviolet light absorbers disclosed in Japanese Patent O.p.l. Publication 6-1 4 8 4 3 0 are also particularly advantageously used. The ultraviolet light absorber may be added to the dopant in a solid form or a solution form in which the ultraviolet light absorbent is dissolved in an organic solvent such as an alcohol, dichloromethane or dioxane. A material such as an organic powder insoluble in a solvent is dispersed in a mixture of an organic solvent and a cellulose ester using a dissolver or a sand mill and added to a dopant. The addition amount of the ultraviolet light absorber varies depending on the kind of the ultraviolet light absorbent used and the use conditions, but when the thickness of the cellulose ester film is 30 to 2 0 0 // m, the addition amount is advantageously 0.5 to 4 0 wt%, and more advantageously 0.6 to 2.0 wt%, based on cellulose ester weight. The cellulose ester film of the present invention may optionally contain fine particles of silica as a matte agent. The surface of the particles of the non-erazant treated with an organic compound is advantageous in providing a reduced turbidity of the film. Examples of organic compounds used in surface treatments printed by employees' consumer cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs include halogenated silanes, alkoxysilyls (especially methylsilanes), silamines, and siloxanes Alkanes. Fine particles having a larger average particle diameter have a high matte effect, and fine particles having a smaller average particle diameter have good transparency. In the present invention, the fine-grained first-order particles have an average first-order particle diameter of favorably 5 to 50 n m, and more favorably 7 to 20 n m. The silica fine particles are not particularly limited, and include, for example, AEROSIL 200, 200V, 3 00, R972, R972V, R972CF, R974, R202, R805, R8 12, 0X50, or TT600 (a separate [J by Nihon Aero si 1 C. , Manufactured by Lt d.) This paper is a national standard (CNS) A4 specification (210X297 mm) -24 593493 A7 B7 5. Description of the invention (22), and the silicon oxide particles are advantageously AEROSIL 200, 200V, R972, R972V, R974, R202, R805 or R812 can add different additives to the dopant containing cellulose ester in batches and add the dopant to the pipeline as a solution containing the additive. In particular with regard to the matte, some or all of the matte is advantageously added to the dopant in the pipeline to reduce the load on the filter used. When the additive solution is added to the cellulose ester dopant in the pipeline, the additive solution advantageously contains a small amount of the cellulose ester solution to increase the compatibility of the additive solution with the dopant. The cellulose ester content of the additive solution is advantageously 1 to 10 parts by weight, and advantageously 3 to 5 parts by weight, based on 100 parts by weight of the solvent. The method of dispersing the non-zeability agent is not particularly limited, but the use of a high-pressure dispersing device such as a dissolver can provide a dispersion in which the non-zeiss agent is dispersed in fine particles. The dispersion may be mixed with a cellulose ester. In order to mix a dopant (where the cellulose ester is dissolved in a solvent) with a solution containing different additives and a small amount of cellulose ester, a mixer in the pipeline such as a static mixer (manufactured by Toray Engineering Co., Ltd. ) Or SWJ (a Toray static tube mixer Hi-Mixer) is advantageously used. When a mixer in a line is used, the resulting mixture is advantageously concentrated under high pressure, and the pressure tank used is not particularly limited as long as it can withstand high pressure, and heating and stirring under increased pressure are possible. The pressure tank is advantageously equipped with a gauge such as a thermometer and a pressure gauge. Example I -------- Installation-- (Please read the precautions on the back before filling this page),?! Printed out of this paper by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs, prepared for national standards (CNS ) A4 specification (210X297 mm) -25 593493 A7 B7 V. Description of the invention (23) The present invention is described in detail by the following examples, but is not limited thereto. Example 1 (Preparation of dopant) (Composition of dopant) Cellulose triacetate (cotton wool, 62.0% 1600 g of osmium acetate) Dipropylene glycol dibenzoate 40 kg 770 kg of methylene chloride, 65 kg or more of the dopant composition was poured into the sealed tank, and stirred to obtain the dopant. The obtained dopant was uniformly cast on a non-recording steel strip with a width of 1 500 mm using a hysteresis casting apparatus at 3 3 ° C to form a thin film. The temperature of the stainless steel strip is controlled at 25 ° C. The cast film was evaporated until the residual solvent amount reached 25%, and it was peeled from the stainless steel strip at a peel tension of 12 7 N / m. The peeled cellulose triacetate film is dried while being transported on a number of rollers in a drying zone. Thus, a cellulose ester film sample 101 was prepared. The thickness of sample 1 0 1 is 4 0 // m. Cellulose triacetate film samples 102 to 1 18 were prepared in the same manner as in cellulose triacetate sample 101 above, except that the additives described in Table 1 were added in place of dipropylene glycol dibenzene. Formate. Cellulose triacetate film samples 1 1 9 were prepared in the same manner as in sample 105 above, except that TINUVIN 109, 171, and 326 (each from Ciba Specialty Chemicals Co., Ltd. System) to the national standard (CNS) Α4 specification (210X297 mm) of this paper (please read the precautions on the back before filling this page)

Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, 1T -26-593493 A7 B7 V. Description of the Invention (24) Adulterants. (Please read the notes on the back before filling out this page.) For samples 1 0 1 to 1 1 9, measure the transfer rate and retention. Regarding samples 1 0 to 1 1 4, the retardation R 0 and the retardation axis angle θ i were measured, and the degree of polarization was calculated from the measured 値. The results are shown in Table 1. (Water vapor transmission rate) The water vapor transmission rate was measured at 25 t: and 90% according to the method described in J I S Z 0 2 0 8. The water vapor transmission rate is advantageously 20 to 2 60 (g / m2 · 24 hours), more advantageously 20 to 2 0 0 (g / m2 · 24 hours), and still more advantageously 20 to 1 5 Ο (g / m2 · 2 4 hours). (Residual property) Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs Each sample is cut into a size of 10 × 10 cm. The cut sample was left at 2 3 ° C and 55% R for 1 day, and then weighed. The obtained samples were heat-treated at 80 ° C and 90% RH for 2 weeks. After that, the samples were allowed to stand again at 23 ° C and 5 5% RH for one day, and then weighed. Retention property is expressed by the following formula: Retention property (%) = (sample weight before heat treatment and sample weight after heat treatment) X 1 0 0 / (sample weight before heat treatment) (blocking RQ, retarded axis angle θ i) Refractometer KOBRA-21ADH (manufactured by Oji Keisokukiki Co., Ltd.), measured at a wavelength of 5 9 in the triaxial direction of samples 1 0 1 to 1 1 4 at 2 3 ° C and 55% R Η The refractive index at 0 nm, and the Λ degree are applicable to the Chinese National Standard (CNS) A4 specification (210X297 mm) · 27 · 593493 A7 B7 V. Description of the invention (25) and determine the retardation phase axis angle θ〇 (°) And Nx, Ny and Nz. On plane R. The block in Chinese is calculated by the previous formula. Furthermore, the degree of polarization is calculated by the following formula (β i (radian) is calculated by Θ Q °): P = l — sin2 (20i) • sin2 (7rR〇 // A) where λ represents the wavelength (nm ) Is 590nm. In the above formula, P is advantageously not less than 0.999, more advantageously not less than 0.999, and even more favorably not less than 0.99 9 9 5 , And most advantageously not less than 0.9 9 9 9 9. (Please read the precautions on the back before filling out this page) Printed on paper by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs ^ / Fukiao Qiaohuang National Standard (€ milk) 8 4 specifications (210 father 297 mm) -28- 593493 A7 B7 V. Description of Invention (26) Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs Inv. Inv. Inv. 1 Inv. Inv. Inv. Inv. Inv. Inv. Inv. Inv. Inv. Inv. Inv. Comp. Comp. Comp. \ Comp. Inv. Additive Additives (g) 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 00 〇00 〇00 ο 00 〇00 〇 | Type 1_ 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 TINUVIN 109 TINUVIN 171 TINUVIN 326 1 Polyol ester addition (g) ο inch O inch ο inch 〇 inch 〇 inch 〇 inch 〇 inch 〇 ○ inch 〇 Inch o Inch o Inch o Inch o Inch o Inch o Inch o Inch o mm \ m. M 11 De 11 E: Π Tripropylene glycol dibenzoate dibutanediol dibenzoate 'tetraethylene glycol dibenzoate Trimethylpropane tribenzoate trimethylpropane triacetate trimethylpropane tripropionate A OQ am mn. O anr mi Q anr draw omega am mi am draw o am draw triphenyl phosphate ethyl Phthalocyanine Ethyl Glycolate Triethyl Acetyl Citrate i Tributyl Acetyl Citrate Trimethyl Alcohol Propane Triphenyl Ester Sample No. r-1 〇r-1 CM 〇τ-1 00 〇τ-1 inch 〇τ-1 LO 〇τ-1 CO 〇τ-1 〇τ-1 00 〇r-1 O) or -1 〇rH τ-H τ-H t-H rH CM rH tH CO τ —1 rH inch i—l rH LO rH r—H CD rH rH BU τ—1 1— \ 00 τ—Η r—1 τ—1 rH (Please read the notes on the back before filling this page) Know China Country Standard (CNS) Α4 specification (210X297 mm) -29- 593493 A7 B7 V. Invention description (27 Printed by the Consumer Cooperative of Intellectual Property Bureau of the Ministry of Economic Affairs

ι— \ a α a Q. &gt; a &gt; a &gt; a &gt; a &gt; a &gt; a &gt; a &gt; a &gt; a &gt; a &gt; a &gt; a &gt; a &gt; a ε ο S ο B os 〇 &gt; a ΗΗ ΗΗ ΗΗ ΗΗ υ υ ο 〇u HH CO r—1 CXI CO CO CO 〇CM CO inch CM ι—Η CO cn CD ① ① a &gt; ① CD ① ① ① ① ① ① cn cn a &gt; cn CD ① cn Ο) ① Ο) ① cn ① ① 〇 &gt; ① ① ① ① ① ① ① ① ① ① ① 1 1 1 1 1 〇o 〇ooo 〇 ο ο ο ^ \ 〇CM o Bu LO ① ο ο ο Ο cn 〇ο ① rH butterfly ^ —1 T—H i—looo rH rH τ—1 .r—1 ο τ—1 τ-Η ο 1 III 1 1 1 1 1 oooooo ο ο ο ο ο ο ο ο N oooooo ο ο ο ο ο ο ο ο 1 0 1 CO 1 CO 1 CO 1 CO 1 CO 1 CO 1 00 bu00 cn rH ^ ~ \ rH CM CM CM τ—Η τ—1 rH τ—1 rH rH τ—Η τ-Η 1 1 1 1 1 c ^ rH CO ① o CD CD γΗ ο τ ~ 1 ι—Η οο τ—1 τ-Η CD CD CO LO o §Ε 次 靼 woooooo Ο ο ο ο ο ο ο ο CO LO LO Inch o -N 4fl7 Hanging, m ^ Z m LO 00 LO 00 LO LO CO 00 ο LO Ln 00 LO 00 τ—Η Ο CO CO LO ^ CM Min Bu CO ① ① CO CO Bu CO CO Bu 00 00 ① ① LO CO 00 〇) inch c * rH t—H τ —H rH t—1 rH rH τ— \ rH τ—1 rH τ—Η τ—1 ^ ~~ 1 CM CM (M τ-Η l— \ it: «; b〇 龟 ng r—1 CM CO inch LjO CO ο 00 cn ο rH CN] CO inch LO CO BU 00 ① oooooo ο ο ο τ—Η τ—1 ι— \ τ—1 r * H τ—Η rH τ—H i—ir—1 t—1 r—1 r ~ H rH t—1 r—1 τ—Η τ-1 τ-Η τ-Η τ—1 rH τ—Η ι— \ τ-Η r— \ τ—H τ-Η 1 ~ \ _ 海 ™ LO jy 田 -U-· Hi ^ ^ (χπ &gt; · C feed η 5 distillate 忉 I ft) fr aldehyde I old CO CO 遐 ·· KQ 鮏 鮏 feed 1Π slightly-| Ιΐ | φ . • • crane co 〇CQ 忉 ~ feeding questions ^ dw ·, Γ 经 I by distilling \ _ &&lt;! □ Η brain crane ~ slightly older W 氍 fr enzyme I £ Ga \ ra ·· J by Jing ... atE roll \ ^ am 郑 镒 凶 Ν] Π 氍 • • Chen Jilin ci 遁 Slightly ^ EfrUl ° ®m I Slightly (Please read the precautions on the back before filling out this page)-Packing. Ordering distillation parts Hi 0 Sand Chinese National Standard (匸 chan) 8 4 specifications (21〇 乂 297 mm) -30- 593493 A7 ___B7 V. Description of the invention (28) As shown in Table 1 above, the cellulose triacetate of the present invention Ester film samples provide low water vapor transmission rates and superior retention properties, compared to comparative cellulose triacetate film samples. Example 2 Each of the cellulose triacetate film samples 1 1 to 1 1 4 and samples 1 1 9 prepared in Example 1 were subjected to alkali saponification, and both sides of the polarized film were adhered to each other via a fully saponified polyvinyl alcohol aqueous solution. The polarizing film has been impregnated and stretched with a polyvinyl alcohol film in an iodine solution. Thus, a polarizing plate sample was obtained. The polarizing plate was peeled off from both sides of a liquid crystal cell of a 15-type TFT color liquid crystal display LA-1 529HM (manufactured by NEC Co., Ltd.). The polarizer sample prepared above was cut according to the size of the liquid crystal cell. Subsequently, each of the polarizing plate samples prepared using the cellulose triacetate film samples 1 0 to 1 1 4 and 1 1 9 prepared in Example 1 was stacked on both sides of the liquid crystal cell so that their polarities The direction of change is based on the original before peeling and perpendicular to each other to obtain the LCD panel. The obtained liquid crystal slats were set in a color liquid crystal display, and a cellulose triacetate film sample used in the polarizing plate was evaluated. As a result, it was confirmed that the liquid crystal display panel using the cellulose triacetate film sample of the present invention exhibits superior display properties and provides a high contrast image, and the cellulose ester film according to the present invention is used as an image display device such as a liquid crystal. The polarizing plate of the display is superior. The effect of the present invention This paper is 4¾reading _ home standard (CNS) A4 specification (210X297 public shame 7 (please read the precautions on the back before filling out this page) 31-593493 A7 B7 V. Description of the invention (29) The present invention can provide cellulose ester film, which provides superior water vapor transmission rate and superior retention. II- — —— (Please read the notes on the back before filling (This page), · ιτ Printed by the Intellectual Property Bureau of the Ministry of Economic Affairs, Consumer Cooperatives, this paper has no Lujia Standard (CNS) Α4 size (210X297 mm) -32-

Claims (1)

/ m 49 3 9 5 A8 B8 C8 D8 VI. Application for Patent Scope 1 Attachment: Patent Application No. 91 106608 Chinese Application for Amendment of Patent Scope Amendment February 5, 1993 Amendment 1. A cellulose ester film including multiple Alcohol esters, which are esters of one or more monocarboxylic acids and aliphatic polyols, in which cellulose ester films have a range of 20 to 26 g when measured at 25 ° C and 90% R9. / m2 · 2 4 hours of water vapor transmission rate, and has a retention of 0 · 0 to 2.0%, and includes a polyol ester content of 3 to 30% by weight based on the weight of cellulose ester. 2. The cellulose ester film according to item 1 of the scope of the patent application, wherein the monobasic acid has an aromatic ring or a ring-based ring in its molecular structure. 3. The cellulose ester film according to item 1 of the application, wherein the aliphatic polyol has a hydroxyl number of 2 to 20. 4. The cellulose ester film according to item 1 of the patent application scope, wherein the cellulose ester film has a thickness of 10 to 65 / m. 5. The cellulose ester film according to item 1 of the application, wherein the aliphatic polyhydric alcohol is represented by the following formula (1): Formula (1) (R 1)-(Ο Η) η where R 1 represents an η-valent lipid Group, and n represents an integer of not less than 2. 6 · If the cellulose ester film according to item 5 of the patent application, wherein the η-valent aliphatic is selected from the group consisting of alkylene, alkylene, alkynyl, cycloalkyl and alkanes, the basic paper standards are applicable to Chinese national standards (CNS ) M specifications (210 x 297 mm) —-(Please read the precautions on the back before filling out this page), 1T f Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 593493 A8 B8 C8 D8 6. Application for patents 2 7. For example, the cellulose ester film of the first patent application range, wherein the polyol ester has a molecular weight of 300 to 1500. 8 alcohols. More 3 is in the middle and less suitable (No, the number of total film is thin, the ester ring is based on retinoyl fibrin ring or the ring of the first ring of the family of Fangwei Li special structure, please subscribing to such as. (Please read first Note on the back, please fill in this page again) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 2 The paper size is applicable to China National Standard (CNS) A4 (210X297 mm)